This invention relates generally to devices and systems for administering medical fluids to a patient by intravenous infusion or the like. More particularly, this invention relates to an improved variable volume bottle for containing a medical fluid, wherein the bottle includes improved means for monitoring the fluid volume dispensed to the patient, and further includes improved and relatively simplified means for variably adjusting the rate of fluid flow to the patient.
Fluid containers such as bottles and plastic bags are well known in the art for use in the administration of a selected medical fluid such as a saline solution or the like to a patient, such as by intravenous infusion. Such fluid containers are typically mounted at an elevated position relative to the patient and include a lower neck or the like adapted for connection to a length of flexible infusion tubing which is coupled in turn to the patient by means of a catheter or the like. The medical fluid within the container is allowed to flow by gravity, in the case of intravenous infusion, through the infusion tubing to the patient. A flow rate regulation means such as a roll clamp mounted along the infusion tubing is normally provided to variably select the rate of fluid flow to the patient. In addition, the fluid container is commonly formed from a transparent or partially transparent material and includes a volumetric scale which can be visually compared with the fluid level within the container. With this arrangement, the volume of fluid administered to the patient and, conversely, the volume of fluid remaining within the container, may be determined. However, these fluid volume determinations are only approximations, particularly when the fluid container is a flexible bag which inherently sags and assumes different physical shapes as the fluid is dispensed.
In recent years, devices and systems for delivering medical fluids to patients have become increasingly complex and costly, particularly with respect to variably regulating and monitoring the rate of fluid flow. More specifically, a variety of electronic drop sensors are currently known for detecting and counting individual fluid drops dispensed from the fluid container to the infusion tubing. While such drop sensors provide accurate monitoring of the fluid flow rate and cumulative volume delivered to the patient, they are relatively sophisticated and costly devices which, unfortunately, continue to rely upon manually adjusted setting of a conventional roll clamp in order to increase or decrease the flow rate, as desired. Adjustment of the roll clamp remains a trial and error process, and typically requires considerable skill to adjust quickly to a specific target flow rate.
The present invention relates to an improved medical fluid container and related system for infusing a medical fluid to a patient, including relatively simple and easily adjustable flow rate regulation means in combination with an improved and relatively simplified means for tracking and monitoring the rate and the volume of fluid flow to a patient.